Front speaker crackle

Hi Guys,

Tried googling my issue but couldn't find any directly related to my issue. So I was driving along yesterday and stopped at some lights and had the engine running (obviously lol) I heard a rattling kind of noise but as I leant over to the passenger side I noticed it was coming purely from the tweeter. I took the radio faceplate off and it stopped. I did some testing today. It always stops when you turn the HU off. It doesn't make its crackling noise when the ignition is powering the radio, only when the engine is on.

Disconnected speakers - Obviously crackle dissapears.
Unplugged RCA's from amp and replugged - still crackling with engine on
Swapped rca cables around on HU (front+rear) and still crackles..
Unplugged and replugged headunit. Crackle turns off when you disconnect headunit with engine on
When you are playing via ignition then turn engine over the crackle starts
Possibly in rear speakers aswell
Fault with HU? Bad ground? Igniton issue?

Wondering if perhaps its an issue with one of the channels on either the HU or AMP..but this still wouldnt explain why it crackles only with the engine on... Maybe its to do with my cars current ignition problem..im going to try plugging in another HU at the weekend and see if the issue goes away..If it does i'll assume a channel on the amps gone. Any helps very appreciated, thanks.

have you done anything at the amp side of it? considering you switched cables at the hu that means that the issue is definitely at or after the amp, so there is no reason to keep working on the hu.

try switching the amps outputs to see if the issue is still there-- that will show if it is a amp problem or a speaker problem.

I cant see why it would be an amp issue if it doesnt crackle with the egine off, possibly bad engine grounds or amp grounds? I swapped all the rca cables on amp around but it still does it. Please note i have two amps next tp each other mounted in the back of the seats one for the subwoofer and one for the four speakers

I tried swapping the channels over but i'm still experiencing the same issue only with the engine on. I've talked to a few audio people and they reckon its a combination of interference issues with the cabling. 1. The two amps are close together where they are mounted (speaker cables from one are right next to power/earth cables on the other.) 2. The RCA cables are pretty bad ones and should invest in better plated ones. 3. the ground cable looks too thin and long for a decent cable. Will be changing all of these things at the weekend and see if theres any difference. If none of these work its probably an amp issue

if u get an extra rca unplug the rca and loop it back into the amp like channel 1(left) and channel 2(right). take one side of the rca from 1 and loop it into 2 . if u hear crackling it's the amp . if u dont then theres an issue with your amp power wire being too close to rca's. also u can try putting inline filters on the rcas just before entering the amp and see if it clears up .